ch. 11

Genus Haemophilus

gram negative coccobacilli -blood loving -many are common microbiota of respiratory tract >H. influenzae causes ear infections, respiratory infections, and meningitis >H. ducreyi causes The STI chancroid

1. micrococcus (obligate aerobes cannot ferment)

gram pos. cocci -found in soil, dust particles, inanimate objects, skin -pigmented colonies -tolerate dry, salty conditions

1. Corynebacterium

gram positive pleomorphic rods -widespread -often club-shaped inform v-shapes or palisades >referred to as coryneforms or diphtheroids -generally facultative anaerobes; some strict aerobes -many harmless and normal microbiota -C. diphtheriae caused diphtheria

Genus Bifidobacterium

gram-positive irregular rods -anaerobes -reside primarily in intestinal tract of humans and other animals -most common members of intestinal microbiota of breastfed infants -thought to exclude pathogens

genera rickettsia, orientia, ehrlichia

include species responsible for several serious anthropod transmitted human diseases -R. rickettsii (rocky mountain spotted fever) -R. prowazekii (epidemic typhus) -O. tsutsugamushi (scrub typhus) -E. chaffeensis (human ehrlichiosis)

lactic acid bacteria

produce lactic acid -gram pos -most can grow in aerobic environments; but usually only ferment -streptococcus inhabit oral cavity; normal microbiota >some pathogenic -lactococcus species used to make cheese -enterococcus inhabit human, animal intestinal tract -lactobacillus rod shaped common in mouth, vagina >break down glycogen deposited in vaginal lining >resulting low pH helps prevent vaginal infections

3. genus vibrio found in marine environments, requires some NA+ for growth

-Gram negative straight or slightly curved rods -pathogens include V. cholerae which causes cholera

anaerobic chemolithotrophs

-chemolithotrophs oxidize inorganic chemicals for energy -anaerobes (no O2 present) use alternative electronic acceptor -most and domain archaea -methanogens are one group

cyanobacteria

-earliest oxygenic phototrophs -introduction of O2 began approximately 3 billion years ago -use water as source of electrons for reducing power -still play essential role as primary producers >harvest sunlight to convert O2 into organic compounds -initially thought to be algae, called blue green algae -diverse group of gram neg bacteria >many convert N2 to ammonia: Nitrogen fixation

anaerobic chemotropes

-early chemotrophs likely used anaerobic respiration -others may have used fermentation -Aerobes contribute by depleting O2 -human body has anaerobic environments >intestinal tract >microenvironments in skin and oral cavity

thriving in terrestrial environments

-microorganisms that live in soil must tolerate a variety of conditions >wet and dry, cold and warm, abundant to sparse nutrients -several genera form structures that help them to survive dry periods >clostridium, bacillus, azotobacter, myxobacteria, streptomyces

anaerobic chemoorganotrophs -fermentation

-oxidize organic compounds for energy like glucose -numerous anaerobic bacteria ferment >ATP made via subtrate level phosphorylation -clostridium are gram pos. endospore forming rods >common in soils >Vegetative cells live in anaerobic microenvironments created by aerobes consuming O2 >endospores can tolerate O2, survive long periods of heat, drying, chemicals, irradiation >germinate when conditions improve >vegetative state is cause of many diseases

genius staphylococcus species inhabit the skin

-skin typically dry, salty; inhospitable to many microbes -staphylococcus are gram-positive cocci >facultative anaerobes >most are harmless normal microbiota >some are medically important

many bacteria inhabit mucous membranes

1. respiratory system -streptococcus, corynebacterium 2. genitourinary system -lactobacillus (vagina) 3. intestinal tract -clostridium, enterobacteriaceae

Genus Coxiella

C. burnetii is only characterized species -obligate intracellular bacterium >can survive outside host cell as spoil like structures called small cell variants form during intracellular growth -not as resistant as underscores to heat, disinfectants -C. burnetii causes Q fever >most often acquired by inhaling bacteria shed from infected animals

3. pseudomonas (obligate aerobes cannot ferment)

Graham negative rods -polar flagella -often produce pigments -most are strict aerobes (no fermentation) -widespread: soil, water -most harmless -some pathogens: P. aeruginosa common opportunistic pathogen

Genus Bacteroides

Gram negative rods and coccobacilli -small -strict anaerobes that inhabit mouth, intestinal tract, genital tract of humans and other animals -important and digestion -makeup approximately 1/3 of bacteria in human feces -maybe responsible for abscesses and bloodstream infections following abdominal surgery

Genus Neisseria

Gram negative, typically kidney bean shaped cocci found in pairs -common microbiota of humans; grow on mucous membranes -typically strict aerobes -some grow anaerobically -N. gonorrhoeae (gonorrhea), N. meningitidis (menigitis) medically important >nutritionally fastidious

Genera Campylobacter and Helicobacter

Microaerophilic Gram negative curved rods -C. jejuni typically lives in intestinal tract of poultry >causes diarrhea in humans -H. pylori causes ulcers >produces urease, which breaks down urea to ammonia to neutralize local pH

2. Mycobacterium (obligate aerobes cannot ferment)

acid fast bacteria -my colic acid and cell wall prevents gram staining (acid fast staining used) -related nocardia species also acid fast -generally pleomorphic rods -many saprophytes, living on dead and decaying matter -notable pathogens: M. tuberculosis, M. leprae -more resistant to disinfectants, often resistant to antimicrobial drugs

Treponema and Borrelia

are gram negative spirochaetes -treponema are obligate anaerobes or microaerophiles -often inhabit mouth and genital tract >T. pallidum causes syphilis >borrelia includes three pathogens, transmitted by arthropods such as ticks and lice >B. recurrentis and B. hermsii cause relapsing fever >B. burgdorferi causes Lyme disease

obligate intracellular parasites

cannot reproduce outside a host cell -most have lost ability to synthesize needed substances >host supplies these compounds

2. family enterobacteriaceae

enterics or enterobacteria -Gram negative rods found in intestinal tract of humans, other animals; some thrive in soil -normal intestinal microbiota include enterbacter, klebsiella, Proteus, most e. coil strains -diarrheal disease caused by shigella, salmonella enterica, and some e. coil strains -life-threatening: typhoid fever (salmonella enterica serotype typhi) and bubonic and pneumonic plague (Yersinia pestis) -facultative anaerobes up for my glucose -lactose for mentors term coliforms >include e. coli >indicator of possible fecal pollution

Genus Mycoplasma

lack cell wall -most common sterols for added strength and rigidity -among smallest forms of life -genomes thought to be minimized size encoding essential functions -colony growth produces characteristic fried eggs appearance -M. pneumoniae causes walking pneumonia >antibiotics at Target peptidoglycan synthesis or not effective

endospore formers

most recent two environmental extremes -bacillus, clostridium are most common -Grand positive rods -clostridium species are obligate anaerobes -bacillus include obligate and facultative anaerobes -bith can cause disease: C. tetani causes tetanus; B. anthracis caused anthrax

Streptomyces

over 500 species of aerobic gram-positive bacteria -growth resembles fungi: form massive branching hyphae called mycelium -chains of spores (conidia) develop at tips -conidia resistant to drying; easily spread by air currents -produce extracellular enzymes, geosmins, and medically useful antibiotics including streptomycin, tetracycline, and erythromycin

Genus Bordetella

small, gram-negative coccobacilli -aerobic -nutritionally fastidious -B. pertussis causes whooping cough in humans -B. bronchiseptica causes kennel cough and dogs

Genera Chlamydia, chlamydophila

transmitted person to person; unique growth cycle -inside house initially as non-infectious reticulate bodies >reproduce by binary fission -later differentiate into dense appearing infectious elementary bodies >released one cell ruptures -chlamydia trachomatis causes eye infections and STI similar to gonorrhea -chlamydophila species causes types of pneumonia

facultative anaerobes

use aerobic respiration but can ferment if O2 is not available